Grinding cam lobes on a cam shaft is usually done by grinding wheels. In accordance with the present invention, the grinding of these cams is carried out by abrasive belts. This machine is more versatile in its ability to grind cams to almost any desired configuration than any machine of which I am aware. The belts are guided along a variable path according to the cam contour desired. Specifically, each belt is guided by a shoe which engages the back side of the belt at its point of contact with a cam periphery. Each shoe is mounted on one end of an elongated actuator which is moved longitudinally by a power unit. This power unit is CNC controlled to move the actuator along its longitudinal axis and cause the shoe to move the abrasive belt toward and away from the cam shaft axis.
In the specific embodiment described hereinafter, the actuators are guided for longitudinal movement by flexor units which urge the actuators in a direction away from the shaft axis.
In accordance with my specific design, the apparatus is intended to grind to predetermined contour a plurality of eccentric cams formed in axially spaced apart relation on an elongated cam shaft. Separate belts are provided for grinding each of the cams, and the shoes which guide the paths of the belts at their points of contact with the cam peripheries are CNC controlled independently of one another. Preferably, the shoes, actuators, and power units for longitudinally moving the actuators are disposed in different planes to permit relatively close grouping without interference.
The object of this invention is to provide a highly versatile and efficient cam grinding machine having the attributes referred to above and which is an improvement on past machines, examples of which are shown in the following U.S. Pat. Nos.:
1,660,291, Birkigt;
1,813,503, Merryweather;
1,843,301, Player, et al;
2,098,438, Stubbs;
2,195,054, Wallace, et al;
2,553,831, Musyl;
3,760,537, Bovatt;
4,091,573, Schmidt;
4,175,358, Bischeri;
4,292,767, Fatula;
4,382,727, Schmidt;
4,607,461, Adams;
4,833,834, Patterson;
British 2 073 069, Thielenhaus.
Other objects of this invention will become more apparent as the following description proceeds.